- Visible-Light-Promoted Polysubstituted Olefins Synthesis Involving Sulfur Ylides as Carbene Trapping Reagents
-
A blue-light-emitting diode (LED) promoted coupling of aryl diazoacetates with sulfur ylides is described. This protocol features mild conditions, good functional group tolerance, and broad substrate scope for both aryl diazoacetates with sulfur ylides. Under optimal reaction conditions, a wide range of trisubstituted olefins is obtained in moderate to good yield, which can be further transferred to other biologically important heterocycles after a two-step simple operation.
- Ye, Cong,Cai, Bao-Gui,Lu, Juan,Cheng, Xiao,Li, Lei,Pan, Zhong-Wen,Xuan, Jun
-
p. 1012 - 1022
(2021/01/09)
-
- Synthesis of functionalized thietanes via electrophilic carbenoid-induced ring expansion of thiiranes with sulfonium acylmethylides as carbene precursors
-
Various functionalized thietanes were prepared from thiiranes via an electrophilic ring expansion with rhodium carbenoids as electrophiles generated from safe and readily accessible dimethylsulfonium acylmethylides. The reaction appears to proceed through electrophilic metallocarbenoid-induced activation of thiiranes, nucleophilic ring-opening of the activated thiiranes with dimethyl sulfide as a transient nucleophile, and nucleophilically intramolecular cyclization. The Umpolung from the nucleophilic ylides to the electrophilic carbenoids plays an important role in both the activation and ring opening of thiiranes and subsequent cyclization. The current method provides a new strategy for the efficient preparation of functionalized thietanes from readily available thiiranes.
- Dong, Jun,Du, Hongguang,Xu, Jiaxi
-
p. 10724 - 10739
(2019/09/30)
-
- Ring-opening cyclization of spirocyclopropanes with stabilized sulfonium ylides for the construction of a chromane skeleton
-
Regioselective ring-opening cyclization of cyclohexane-1,3-dione-2-spirocyclopropanes with stabilized sulfonium ylides provided 2,3-trans-disubstituted 2,3,4,6,7,8-hexahydro-5H-1-benzopyran-5-ones in high yields without the formation of any isomers. The o
- Nambu, Hisanori,Onuki, Yuta,Ono, Naoki,Tsuge, Kiyoshi,Yakura, Takayuki
-
supporting information
p. 6539 - 6542
(2019/06/13)
-
- New Pd(II) complexes of sulfur ylides; Synthesis, X-ray characterization, a theoretical study and catalytic activity toward the Mizoroki-Heck reaction
-
The reaction of sulfur ylides (L) SMe2C(H)C(O)R (R = 4-nitrophenyl, phenyl, and 3-nitrophenyl) with the dichloro(1,5-cyclooctadiene)palladium(II) complex, [PdCl2(cod)], in a 2:1 ratio gives the new Pd(II) complexes of type cis- and trans-[PdCl2(SMe2C(H)C(O)R)2] (R = phenyl (1), 3-nitrophenyl (2), and 4-nitrophenyl (3)). Characterization of the obtained complexes was performed by elemental analysis, IR, 1H, 13C NMR and mass spectroscopies. Also, the structure of complex trans-[PdCl2(SMe2C(H)C(O)C6H4-p-NO2)2] (3) was characterized by single crystal X-ray analysis. The X-ray crystallography results reveal that the structure of complex 3 contains two Cα-coordinated sulfur ylide ligands in trans geometry. These air/moisture stable complexes were also employed as efficient catalysts for the Mizoroki-Heck cross-coupling reaction of several aryl halides with olefins. The coupled products of these reactions were obtained in good to excellent yields and purity, short reaction times and low catalyst loading. Also a theoretical study on the structure of the complexes 1-3 have been investigated at the BP86/def2-SVP level of theory. The bonding situation between the [PdCl2] and L2 fragments [(Ylide)2] in the [L2PdCL2] complexes, were carried out by NBO and energy-decomposition analysis (EDA), as well as their natural orbitals for chemical valence variation (EDA-NOCV). The results confirmed that the contribution of the electrostatic interactions in the Pd-C bond in the complexes is about 50%.
- Sabounchei,Ahmadianpoor,Yousefi,Hashemi,Bayat,Sedghi,Akhlaghi Bagherjeri,Gable
-
p. 28308 - 28315
(2016/04/09)
-
- 1,6-Conjugated Addition-Mediated [2+1] Annulation: Approach to Spiro[2.5]octa-4,7-dien-6-one
-
A formal 1,6-conjugated addition-mediated [2+1] annulation to synthesize spiro[2.5]octa-4,7-dien-6-one with p-quinone methides and sulfur ylides has been described. This domino-type process was highly diastereoselective and exhibited good functional group tolerance and scalability without the use of metals and bases.
- Yuan, Zhenbo,Fang, Xinxin,Li, Xuanyi,Wu, Jie,Yao, Hequan,Lin, Aijun
-
p. 11123 - 11130
(2015/11/18)
-
- Functionalized α-keto stabilized sulfonium ylides as highly active ligand precursors for palladium catalyzed Suzuki-Miyaura cross-couplings
-
Five α-keto stabilized sulfonium ylides as type (Me) 2SCHC(O)C6H4-p-X (X = H, Br, NO2, CH3 and OCH3) {L1-L5} were used as ligand precursors in the Suzuki-Miyaura cross-coupling reaction. The best catalytic performance was obtained by using a sulfonium ylide/Pd ratio of 2:1. The catalytic systems displayed high activities, which increased in the order R = NO2 (L3) 2) 1) 3 (L4) 3 (L5). The coupling reactions proceeded smoothly with 0.05 mol% PdCl2 and 0.1 mol% L5 in DMF at 130 °C between varieties of electronically activated, deactivated and neutral aryl halides and aryl boronic acids within short reaction times and without the need for exclusion of air which gave good to high yields of the corresponding products. All the studied ligands demonstrated very high activity in the Suzuki-Miyaura cross-coupling, which yielded turnover numbers up to 1940. Comparative studies showed that the performance of sulfonium ylide L5 is significantly superior to that of related phosphine-free ligands.
- Sabounchei, Seyyed Javad,Hashemi, Ali
-
p. 123 - 127
(2014/08/18)
-
- Synthesis and characterization of novel simultaneous C and O-coordinated and nitrate-bridged complexes of silver(i) with carbonyl-stabilized sulfonium ylides and their antibacterial activities
-
Reaction of sulfonium ylides (Me)2SCHC(O)C6H 4R (R = H; m-NO2; p-NO2; p-OMe; p-Me and p-Br) with AgNO3 in dichloromethane leads to various compounds. Single crystal X-ray diffraction analysis reveals that the adducts take 3 forms: (i) two-dimensional polymer, [AgNO3(Me2SCHC(O)C 6H5)]n (1), with nitrate bridges in which each nitrate coordinates to three silver atoms through two oxygen atoms and two Me2SCHC(O)C6H5 ligands coordinate to silver centers through carbon atoms; (ii) cationic binuclear, [Ag(Me 2SCHC(O)C6H4-m-NO2) 2]2(NO3)2·2H2O (2), in which Me2SCHC(O)C6H4-m-NO2 ligands simultaneously coordinate through both carbon and oxygen atoms with nitrate as a counter ion, and (iii) cationic mononuclear and anionic binuclear, [Ag(Me2SCHC(O)C6H4-p-NO2) 2]2[{AgNO3(μ-NO3) (Me 2SCHC(O)C6H4-p-NO2)} 2]·2CH3OH (3), in which nitrate groups act as bridging as well as terminal ligands, and Me2SCHC(O)C 6H4-p-NO2 ligands display C-coordination. Characterization of the obtained compounds was also performed by infrared, 1H- and 13C-NMR spectroscopy and analytical data indicated a 1:2 stoichiometry between the silver(i) nitrate and ylide p-OMe (4) and 1:1 for ylides p-Me (5) and p-Br (6). In addition, the antibacterial effects of DMSO-solutions of complexes 1-6 were evaluated by the agar disc diffusion method against three Gram positive and three Gram negative bacteria. All complexes displayed antibacterial activity against these bacteria, with high levels of inhibitory potency exhibited against the Gram negative species.
- Sabounchei, Seyyed Javad,Akhlaghi Bagherjeri, Fateme,Mozafari, Zeinab,Boskovic, Colette,Gable, Robert W.,Karamian, Roya,Asadbegy, Mostafa
-
p. 2520 - 2529
(2013/04/10)
-
- Gold-catalyzed carbene transfer to alkynes: Access to 2,4-disubstituted furans
-
Furans of gold: The first example of a gold-catalyzed intermolecular addition of carbon ylides to terminal alkynes is reported (see scheme; DCE=dichloroethane, Tf=trifluoromethanesulfonyl). Subsequent intramolecular trapping of the generated gold carbene completes a formal [3+2] cycloaddition, which represents a novel synthesis of 2,4-disubstituted furans. Copyright
- Kramer, Soren,Skrydstrup, Troels
-
p. 4681 - 4684
(2012/06/30)
-
- Laser flash photolysis study of dialkylphenacylsulfonium salts
-
Laser flash photolysis of the title compound in degassed acetonitrile at room temperature revealed the presence of transient species showing the absorption at 480 nm, regardless of the structure of the precursors. The transient bands are assigned to phenacyl radical presumably formed as a result of the carbon-sulfur bond rather than 1,4-biradicals or cationic species proposed to be formed as a result of Norrish Type II process.
- Kawamura, Koichi,Kodama, Kunihiko,Hirai, Katsuyuki,Tomioka, Hideo
-
p. 148 - 149
(2007/10/03)
-
- Unusual fluorescent properties of novel fluorophores, 6-aryl-3,4-diphenyl-α-pyrone derivatives
-
Novel fluorophores, 6-aryl-3,4-diphenyl-α-pyrones, were synthesized and their spectroscopic properties investigated in the form of evaporated films on plain glass slides, as well as in the solid and solution states. An electron-donating aryl group on the 6-position of the pyrones causes a red-shift in the absorption and fluorescent maxima. In the solid states, they show intense blue-to-orange fluorescence, but not in solution. This unusual fluorescent property is caused by fixing the 6-aryl group of the pyrones, and is the result of molecular packing. These interactions induce a pathway for radiative decay, which is associated with intense fluorescence emission only in the solid state.
- Hirano,Minakata,Komatsu
-
p. 1567 - 1575
(2007/10/03)
-
- Thermal Ring-Expansion of N-Acyl Cyclopropyl Imines
-
The FVT of N-acyl cyclopropyl imines with methyl, phenyl, and acyl substituents at C-1 or C-2 of the cyclopropyl ring has been studied.The parent N-acyl cyclopropyl imine and N-acyl methylcyclopropyl imines gave no ring-expansion products but ring-opened mixtures, decomposed fragments, and polymerization tars after FVT, whereas N-acyl phenylcyclopropyl imines and N-acyl acylcyclopropyl imines generated ring-expansion products, 2-pyrrolines.It demonstrates the first study on the thermal rearrangement of N-acyl cyclopropyl imines.
- Wu, Pei-Lin,Wang, Wen-Shan
-
p. 622 - 627
(2007/10/02)
-
- Metal-Ylide Complexes: Mercury(II), Cadmium(II) and Palladium(II) Complexes of Ambidentate Sulphonium Ylides
-
Synthesis of Hg(II), Cd(II) and Pd(II) halide complexes with stable sulphur ylides, phenacylidene dimethylsulphurane and 4-methoxyphenacylidene dimethylsulphurane is described.The function of sulphonium group as the non-coordinated counter ion is supported by IR and NMR data.The ν (C=O) bands of the complexes are higher than those of free ylides and approach those of the completely protonated onium salts.This indicates coordination via methine carbon atom.The structures of the complexes have been elucidated on the basis of elemental analyses, anion exchange and IR and NMR data.
- Singhal, R. K.,Awasthi, Alok K.,Mishra, Naresh K.
-
p. 1046 - 1048
(2007/10/02)
-
- METAL-YLIDE COMPLEXES: MERCURY(II), CADMIUM(II), COBALT(II), AND NICKEL(II) COMPLEXES OF AMBIDENTATE SULFONIUM YLIDES
-
The mercury(II), cadmium(II), cobalt(II) and nickel(II) halide complexes with stable sulfur ylides have been prepared from phenacylidenedimethylsulfurane, 4-chlorophenacylidenedimethylsulfurane, 4-metylphenacylidenedimethylsulfurane, and 4-methoxyphenacyl
- Tewari, Ram S.,Awasthi, Alok K.
-
p. 403 - 408
(2007/10/02)
-
- Studies on Carbonyl Stabilized Sulphonium Ylids : Reaction with α,β-Unsaturated Carbonyl Compounds
-
1,2,3-Trisubstituted-cyclopropanes (3a-j) have been prepared by the reaction of the sulphur ylids phenacylidenedimethylsulphurane (1a) and 4-methylphenacylidenedimethylsulphurane (1b) with α,β-unsaturated ketones (2).The carbonyl stabilized ?-sulphuranes (1) have been generated from their corresponding salts.Structural assignments of the products are based on their IR and PMR data.
- Tewari, R. S.,Awasthi, A. K.
-
p. 168 - 169
(2007/10/02)
-
- Studies on Stabilized ?-Sulphuranes: Cyclopropanation with Dimethylphenacylidenesulphurane
-
Dimethylphenacylidenesulphurane (2), a stabilized ?-sulphurane has been prepared and reacted with a variety of substituted α,β-unsaturated ketones to afford 1,2,3-triaryl substituted cyclopropanes in fair to good yields.The structural assignments are based on spectral analysis.
- Tewari, R. S.,Awasthi, A. K.
-
p. 155 - 156
(2007/10/02)
-